Relay with surge suppressor

ABSTRACT

A relay characterized by removable modular contact assemblies and a removable modular surge suppressor assembly which is substitutable for one of the modular contact assemblies, and the modular surge suppressor assembly comprising diode means electrically connected in parallel with an electromagnetic coil comprising an operating part of the relay.

United States Patent [191 Grunert et al.

11 3,733,516 [4 1 May 15, 1973 [54] RELAY WITH SURGE SUPPRESSOR [75] Inventors: Kurt A. Grunert, Beaver; Robert W. Schaltenbrand, Glenshaw, both of Pa.

[73] Assignee: Westinghouse Electric Corporation,

Pittsburgh, Pa.

[22] Filed: July 11, 1972 [21] Appl. No.: 270,775

[52] US. Cl. ..3l7/l6, 317/31, 317/58, 317/6l.5, 317/71, 3l7/DlG. 6

[51] Int. Cl. ..H02h 1/04, HOZh 9/04 [58] Field of Search ..3l7/13 R, 14 B, 58, 317/15, 16, 71, DIG. 6, 61.5, 31; 335/132,

[5 6] References Cited UNITED STATES PATENTS 3,519,967 7/1970 Mullen ..335/132 Primary Examiner-James D. Trammell Assistant Examiner-Harvey Fendelman A ttorney-A. T. Stratton et al.

[5 7] ABSTRACT A relay characterized by removable modular contact assemblies and a removable modular surge suppressor assembly which is substitutable for one of the modular contact assemblies, and the modular surge suppressor assembly comprising diode means electrically connected in parallel with an electromagnetic coil comprising an operating part of the relay.

10 Claims, 10 Drawing Figures lOl SHEET 2 OF 3.

PATENTED HA I 51m fi J ///J 7 PATENTED MAY I 51975 SHEET 3 [if 3 FIGS.

FIGS.

F IG.8.

1 RELAY WITH SURGE SUPPRESSOR BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a relay having means for suppressing voltage surges and more particularly it pertains to a relay having a removable modular surge suppressor assembly.

2. Description of The Prior Art The use of surge suppressors as overvoltage protection is well known in the art. For example, in US. Pat. No. 3,184,642 there is disclosed an overvoltage protector for a current transformer. A disadvantage of that structure is that the overvoltage protector protects only the current transformer and does not prevent high voltage spikes from entering related electrical equipment such as solid state components.

Voltage induced with an inductance type element depends not only on the inductance value, but also more critically on the charging current with respect to time. Thus, each time a circuit is opened or closed through a coil, a very high voltage is possible generated which may cause damage to related electrical equipment.

SUMMARY OF THE INVENTION Generally, in accordance with this invention it has been found that the foregoing problem may be overcome by providing a relay comprising an insulating housing having a plurality of chambers separated by insulating barrier wall portions of the housing, an electromagnetic control mechanism supported in the housing and comprising an electromagnetic coil and an armature structure movable in opposite directions for energizing and deenergizing the control mechanism, a modular surge suppressor assembly comprising an insulating suppressor housing, surge suppressor means in the suppressor housing for suppressing a breakdown voltage in the coil, the surge suppressing means being electrically connected inparallel with the electromagnetic coil, the surge suppressor assembly being removably mounted in one of the chambers, a modular contact assembly comprising an insulating contact housing, a stationary contact supported in said contact housing, a movable contact structure, a contact carrier supporting said movable contact structure and being movable in the contact housing to move said movable contact structure between twooperating positions into and out of engagement with said stationary contact, and one modular contact assembly being removably mounted in the remaining chambers of the insulating housing.

The advantage of the device of this invention is that the modular surge suppressor assembly is detachably mounted in the relay insulating housing rather than on a panelboard on which the relay is mounted and thereby results in a more compact structure and does not occupy extra panel space.

DRAWINGS FIG. 1 is a top plan view of a relay constructed in accordance with principles of this invention with one of the modular contact assemblies and the modular surge suppressor assembly being shown in exploded positions;

FIG. 2 is a sectional view taken along the line Il-II of FIG. 1 with the removed modular surge suppressor assembly being shown in an exploded position;

FIG. 3 is a view, with parts broken away, of parts of one of the modular contact assemblies;

FIG. 4 is a top plan view of parts of the modular contact assemblyseen in FIG. 3;

FIG. 5 is a sectional view illustrating parts of the relay of FIG. 2 with the relay in an unactuated position;

FIG. 6 is a view similar to FIG. 5 with the relay in the actuated position;

FIG. 7 is a view similar to FIG. 5 with the modular contact assembly shown in the reversed position;

FIG. 8 is a view similar to FIG. 7 with the relay being shown in the actuated position;

FIG. 9 is a partial sectional view taken generally along the line IX-IX of FIG. 1 with an additional contact layer added in order to provide for eight pole operation; and

FIG. 10 is an end view along the line XX of FIG. 3 looking in the direction of the arrows.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is illustrated as applied to a relay having an operating and contact mechanism of the type fully disclosed in U.S. Pat. No. 3,519,967, issued July 7, 1970, to John H. Mullen and Z. .Iohn Kruzic, and assigned to the assignee of the instant invention. For a complete understanding of the structure and operation of the relay mechanism, reference is made to said US. Pat. No. 3,519,967.

Referring to the drawings, there is shown, in FIGS. 1 and 2, a four pole relay 5 with one of the modular contact assemblies removed. The relay 5 comprises a metallic mounting plate 7 and an insulating relay housing 9 mounted on the plate 7. The relay housing 9 comprises a molded insulating base 11 and a molded insulating top 13. A pair of mounting screws 15 secure the housing parts 11, 13 together and mount the housing 9 on the base 7. An electromagnetic control mechanism 17 is supported in housing 9.

The control mechanism 17 comprises a generally U- shaped magnetic laminated core member 19 and an armature structure 21 that comprises a generally U- shaped magnetic laminated armature 23 and an insulating operating member 25 connected to the armature 23 by means of a pin 27. A pair of coils 29 and 31 are embedded, during a molding operation, in the molded housing base 11 as integral parts of the housing base 11. The parts are mounted with each of the coils positioned over a different leg of the U-shaped yoke 19. The upper housing part 13 is molded with a plurality of barriers 35 forming four cavities 37 that are separated by the barriers 35 and that are provided to receive three modular contact assemblies 39 and one surge supporessor assembly 40. One modular contact assembly 39 is shown in position in FIG. 1. Another modular contact assembly 39a is shown in its removed or exploded position. A section line is taken through the empty cavity 37. The modular surge suppressor assembly 40 is shown in FIGS. 1 and 2 exploded from the mounted position for the purpose of clarity. In FIG. 1 the insulating operating member 25 extends across the relay and is provided with a separate window-opening 41 in each of the four cavities 37. A pair of metallic inserts 43 are fixedly secured to the housing part 13 at the bottom of each of the cavities 37. Each of the metallic inserts 43 is provided with a tapped opening therein for receiving a separate threaded pole terminal screw 44.

Each of the modular contact assemblies 39 (FIGS. 3-4) comprises a molded insulating contact housing 45 having a cavity 47 therein. A separate terminal conductor 49 is supported at each of the two opposite ends of each contact housing 45. Eachof the terminal conduc tors 49 is generally U-shaped, and a stationary contact 51 is fixedly secured to one leg of each conductor 49. As shown in FIG. 3, the opposite legs of each terminal conductor 49 are generally parallel in proximity to the free ends thereof and they are bent over to provide slanted parts 53 between the end parts of the legs and the bight portion 55. Each of the legs 52, 53 of each terminal conductor 49 is provided with opening means 57 which means comprise a generally circular opening part 59 and an elongated opening part 61. Each insulating contact housing 45 is provided with an opening 63 (FIG. 3) at each of the two opposite ends of the housing 45. A separate molded insulating contact carrier (FIGS. 3 and having a window-opening 67 therein, is positioned in the cavity 47 of each of the contact housings 45. A separate bridging contact member 69, having a pair of contacts 71 supported on the opposite ends thereof, is positioned in each window-opening 67. A separate insulating generally U-shaped spring retainer 73 is positioned in each window-opening 67, and a separate coil compression spring 75 is supported between each spring retainer 73 and the associated bridging contact member 69.

When it is desired to assemble the modular contact assembly 39, the spring retainer 73 and bridging contact member 69 are placed in position on the contact carrier 65 with the spring 75 disposed between the members 73, 69. Thereafter, the contact carrier 65 is moved up through the cavity 47 into the contact housing 45, and the two terminal conductors 49 are moved endwise into position in suitable slots in the contact housing 45 to position the stationary contacts 51 under the movable contacts 71 to retain the contact carrier 65 in position. The modular contact assembly 39 is then moved endwise into the associated cavity 37 to the position shown in broken lines in FIG. 1. Thereafter, the pole terminal screws 44 are moved into position going through the circular openings 59 (FIG. 4) in the upper legs of the terminals 49 and through the elongated openings 61 in the lower legs of the terminals 49 and through the elongated openings 61 in the lower legs of the terminals 49 to be screwed into the tapped inserts 43. As shown in FIGS. 1 and 2, each of the pole terminal screws 44 comprises a threaded shank with a screwhead and an inverted generally U-shaped member 79 that is positioned over the shank under the screwhead to engage a conducting wire that would be positioned under the member 79 and adjacent the associated flat slanted surface 53 (FIG. 3) of the terminal conductor 49. With the contact assembly 39 in the position shown in FIGS. 5 and 6, the pole unit is provided for normally open operation.

When it is desired to change the operation of the pole unit, the pole terminal screws 44 are removed and the modular contact assembly 39 is moved endwise out of the associated cavity 37 and turned over; then moved endwise back into the associated cavity 37 to the position shown in FIGS. 7 and 8. In this case, each pole terminal screw 44 passes through the circular opening 58 (FIG. 4) in the leg that supports the stationary contact and through the elongated opening 61 in the other leg, and into the associated tapped insert 43 to secure the modular contact assembly 39 in position. It is noted that the slanted surface 53 of the leg that supports the stationary contact'o'f each of the terminals 49 is positioned adjacent the associated member 79 (FIGS 7 and 8) to receive a conducting wire that is placed between the surface 53 and the member 79 to connect the associated terminal conductor 49 to the conducting wire. The modular contact assembly 39 is reversible by re moving the pole terminal screws 44 and thereafter removing and turning over the contact assembly 39 before replacement and mounting of the screws 44, without necessitating a disassembly of the parts of the modular contact assembly. With the slanted surfaces 53 provided and with the pole terminal screws 44 extending at an angle as shown in the drawings, it is noted that when another contact layer is mounted over the first layer (FIG. 9) the screws 44 of the lower layer are readily accessible for adjustment with a screwdriver type tool.

As shown in FIGS. 5-8, when the modular contact assembly 39 is moved into the associated cavity 37, the contact assembly 39 moves through a window-opening 41 in the insulating operating member 25 and the contact carrier 65 is aligned with the operating member 25 so that vertical reciprocal movement of the insulating operating member 25 will operate to vertically reciprocate the contact carrier 65.

Referring to FIG. 5, the relay 5 is shown in the unactuated position with a nesting coil-type kickout spring 79 positioned between the housing base 11 and the bight portion of the armature 23 to bias the armature structure 21 to the upper unactuated position shown. With the armature structure 21 in the upper position, the insulating contact carrier 65 is maintained in the upper position wherein the movable contacts 71 are spaced from the stationary contacts 51. Upon energization of the coils 29, 31 (FIG. 2) the armature 23 is attracted toward the yoke 19 whereupon the armature structure 21 is moved to the actuated position seen in FIG. 6 compressing the kickout spring 79 that moves into the nested compressed position shown in FIG. 6. During this movement of the armature structure 21, the contact carrier 65 is moved down to move the contacts 71 into engagement with the contacts 51, and the contact carrier 65 is moved an additional distance to provide overtravel and contact pressure during which additional movement the contact spring is further compressed. As can be seen in FIG. 6, the spring 75 is compressed between the bridging contact structure 69 and the spring retainer 73 which engages the upper end of the contact carrier 65. When the coils 29, 31 are deenergized, the kickout spring 79 returns the armature structure 21 and contact carrier 65 to the upper unactuated position seen in FIG. 5. During the initial part of this movement, the kickout spring 79 and contact springs 75 serve to move the armature structure 21 toward the upper position seen in FIG. 5 until the bridging contact member 69 engages the contact carrier 25 at the bottom of the window-opening 67, and thereafter the kickout spring 79 alone serves to move the armature structure to the upper unactuated position seen in FIG. 5.

When the modular contact assembly 39 is mounted on the relay in the reversed position (FIG. 7) andthe relay is in the unactuated position, the kickout spring 79 biases the armature structure 21 to the upper position seen in FIG. 7 in which position the contacts 51,

71 are closed. In the position seen in FIG. 7 the armature structure 21 is in the full upper position and the contact carrier 25 is moved upward slightly past the initial closed position of the contacts with the contact spring 75 being compressed slightly to provide overtravel and contact pressure. When the relay is energized, the armature structure 21 is operated down to the actuated positions seen in FIG. 8. During the initial part of this movement, the spring retainer 73 moves with the contact carrier 25 until the opposite legs of the spring retainer engage the housing part 13 of the relay (FIG. 8) and thereafter the spring retainer 73 remains stationary while the contact carrier 25 is moved to the fully actuated position seen in FIG. 8. During this movement, the contact spring 75 is compressed and the contacts are moved to the fully opened position. When the relay is then deenergized the compressed kickout spring 79 and the compressed contact spring 75 operate to move the armature structure 21 upward, and when the contact carrier 25, at the bottom of the window-opening, engages the spring retainer 73 the kickout spring 79 thereafter alone serves to move the armature structure 21 to the unactuated normally closed position seen in FIG. 7. During the movement to the normally closed position seen in FIG. 7 the contacts 71 first engage the contacts 51 and there is a slight additional movement upward during which movement the contact spring 75 is additionally compressed to permit overtravel and provide contact pressure in the closed position.

As will be understood with reference to FIGS. 1 and 2, the hereinbefore described relay is a four pole relay with the common operating member 25 moving to simultaneously move the four contact carriers 65 of the four modular contact assemblies 39 during operation of the relay. The four modular contact assemblies 39 can be mounted on the relay to provide four normally open poles, four normally closed poles, or a mixture of normally open and normally closed poles depending on the particular control requirement.

Referring to FIGS. 1 and 2, it is noted that the insulating operating member 25 is provided with an opening 85 therein, and a nut 87 is captured in the operating member 25 at the bottom of the opening. In FIG. 9, another contact layer 89 of pole units comprises an insulating housing 91 having four cavities 93 therein similar to the cavities 37 for receiving four modular contact assemblies 95 that are identical to the contact assemblies 39. An eight pole relay is disclosed in FIG. 9.

Tapped inserts 97 are supported on the housing 91 for receiving pole terminal screws 99 that mount the modular contact assemblies 95 to the housing 91 in the same manner as was hereinbefore described with regard to the modular contact assemblies 39. An operating member 101, similar to the operating member 25, having four window-openings for receiving the four modular contact assemblies 95, is mounted on the housing 91 for reciprocal vertical movement. The housing 91 is mounted on the relay housing part 13 by means of two bolts 103 (only one of which is seen in FIG. 9) with the operating member 101 being positioned on top of the operating member 25 and with an opening in the operating member 101 aligned with the opening 85 (FIG. 1) in the operating member 25. A bolt 107 is extended through the aligned openings in the operating members 101 and 25, and threaded into the nut 87 to secure the operating members 101 and 25 together. Thus, when the armature structure 21 is vertically reciprocated in the manner hereinbefore described, the operating member 101 moves with the operating member 25 and the four modular contact assemblies of the upper layer 89 are simultaneously operated with the four modular contact assemblies 39. It can be understood that an additional contact layer 89 could be mounted on top of the two layers seen in FIG. 9 to provide a twelve pole relay in the same general manner as was hereinbefore described with regard to the eight pole relay.

In order to prevent possible damage to other components in a system which includes the relay 5, the surge suppressor assembly 40 is provided as a replacement for one of the modular contact assemblies 39 such as shown in FIGS. 1 and 2. The modular surge suppressor assembly 40 is structurally interchangeable with the modular contact assembly 39 and comprises a molded electrically insulating housing 109 having a cavity 111 therein. A separate terminal conductor 113 and 115 is supported at each of the opposite ends of the housing 109. Each terminal conductor 113 and 115 is generally U-shaped with opposite legs substantially parallel to the free ends thereof. More particularly, the modular surge suppressor assembly 40 has an overall size and shape comparable to that of the modular contact assemblies 39. For convenience,'the insulating housing 109 and the terminal conductors 1 13 and 1 15 are similar in construction to comparable parts in the modular contact assembly 39. Accordingly, the terminal conductors 1 13 and 115 are provided with opening means similar to the opening means 57 for the purpose of receiving the threaded pole terminal screws 44 by which the modular surge suppressor assembly 40 is retained in place within the cavity 37 as shown in FIG. 2.

The modular surge suppressor assembly 40 differs from the modular contact assembly 39 in that the former includes surge suppressor means 1 17 instead of the stationary and movable contacts 51 and 71, as well as the insulating contact carrier 65, the bridging contact member 69 and the spring retainer 73. In fact, the modular surge suppressor assembly 40 includes no movable operating parts. Rather, the assembly 40 merely includes the surge suppressor means 117 within the cavity 111 which means comprises suitable voltage suppressors such as a pair of diodes 119 and 121 as well as a resistance 123. As shown in FIG. 2, the diodes 119 and 121 as well as the resistance are connected in series by a wire 125, the opposite ends of which are secured to the terminal conductors 113 and 115 respectively. Connection of the wires to the conductors is made in any suitable manner such as by solder joints 127. It is noted that the diodes 119 and 121 are connected in back-toback positions for accommodating alternating current. It is understood however that where direct current is used, only one diode is necessary.

The resistance 123 is a current limiting resistor which is available in the event that one or both of the diodes suddenly fails and thereby creates a short circuit. In that event, the resistor limits the current flowing through the surge suppressor assembly 40 to a relatively low value.

Means other than diodes which may be used as substitutes for the diodes as surge suppressors include nonlinear resistors, and capacitors, both of which absorb high voltage spikes which may be generated at the moment a circuit through the coil 29 and 31 is open or broken.

Finally, the modular surge suppressorassembly 40 may be connected in parallel with the coils 29 and 31 by providing lead wires (not shown) between the terminal members 79 of the assembly and terminal screws 32 of the coils.

Accordingly, the device of this invention satisfies the problem of prior art structures by preventing high voltage spikes from entering the related electrical equipment such as solid state components in a system in which the relay is an integral part, which advantage is obtained without the addition of other units and merely by substituting one modular surge suppressor assembly for a modular contact assembly.

What is claimed is:

1. A relay comprising an insulating housing, an electromagnetic control mechanism supported on said housing and comprising an electromagnetic coil and an armature structure movable in a first direction upon energization of said control mechanism and in a second direction opposite of the first direction upon deenergization of said control mechanism, the insulation housing having cavity means for receiving at least two modular assemblies, a modular surge suppressor assembly comprising an insulating suppressor housing, surge suppressor means in the suppressor housing for suppressing a breakdown voltage in the coil, the surge suppressor means being electrically connected in parallel with the electromagnetic coil, the surge suppressor assembly being removably mounted in the cavity means, at least one modular contact assembly comprising an insulating contact housing, a stationary contact supported in said contact housing, a movable contact structure, a contact carrier supporting said movable contact structure and being movable in said contact housing to move said movable contact structure between two operating positions into and out of engagement with said stationary contact, and the modular contact assembly being removably mounted in the cavity means. i

2. The relay of claim 1 in which the surge suppressor means comprises diode means.

3. The relay of claim 2 in which the diode means comprises at least one diode.

4. The relay of claim 1 in which the surge suppressor means comprises a pair of diodes of opposite polarities mounted in back-to-back positions.

5. The relay of claim 4 in which the surge suppressor means comprises a resistance in series with the diodes.

6. The relay of claim 1 in which the cavity means comprises at least two chambers separated by an insulating barrier.

7. The relay of claim 6 in which the control mechanism extends into the chambers.

8. The relay of claim 7 in which the modular surge suppressor assembly is in one of the chambers and the modular contact assembly is in the other of the chambers.

9. The relay of claim 1 in which the electromagnetic coil comprises a pair of terminal conductors, the modular surge suppressor assembly comprises a pair of terminal conductors one of which is connected to one of the terminal conductors of the electromagnetic coil and the other of which is connected to the other terminal conductor of said coil.

10. The relay of claim 1 in which modular surge suppressor assembly is structurally interchangeable with the modular contact assembly. 

1. A relay comprising an insulating housing, an electromagnetic control mechanism supported on said housing and comprising an electromagnetic coil and an armature structure movable in a first direction upon energization of said control mechanism and in a second direction opposite of the first direction upon deenergization of said control mechanism, the insulation housing having cavity means for receiving at least two modular assemblies, a modular surge suppressor assembly comprising an insulating suppressor housing, surge suppressor means in the suppressor housing for suppressing a breakdown voltage in the coil, the surge suppressor means being electrically connected in parallel with the electromagnetic coil, the surge suppressor assembly being removably mounted in the cavity means, at least one modular contact assembly comprising an insulating contact housing, a stationary contact supported in said contact housing, a movable contact structure, a contact carrier supporting said movable contact structure and being movable in said contact housing to move said movable contact structure between two operating positions into and out of engagement with said stationary contact, and the modular contact assembly being removably mounted in the cavity means.
 2. The relay of claim 1 in which the surge suppressor means comprises diode means.
 3. The relay of claim 2 in which the diode means comprises at least one diode.
 4. The relay of claim 1 in which the surge suppressor means comprises a pair of diodes of opposite polarities mounted in back-to-back positions.
 5. The relay of claim 4 in which the surge suppressor means comprises a resistance in series with the diodes.
 6. The relay of claim 1 in which the cavity means comprises at least two chambers separated by an insulating barrier.
 7. The relay of claim 6 in which the control mechanism extends into the chambers.
 8. The relay of claim 7 in whIch the modular surge suppressor assembly is in one of the chambers and the modular contact assembly is in the other of the chambers.
 9. The relay of claim 1 in which the electromagnetic coil comprises a pair of terminal conductors, the modular surge suppressor assembly comprises a pair of terminal conductors one of which is connected to one of the terminal conductors of the electromagnetic coil and the other of which is connected to the other terminal conductor of said coil.
 10. The relay of claim 1 in which modular surge suppressor assembly is structurally interchangeable with the modular contact assembly. 